What is Glutamine and its Major Functions,
Glutamine is a non essential amino acid that is the most copious amino acid found in the human body and possesses many functions (Chwals, 2004). It can be present in muscle tissues, plasma, and even cerebral spinal fluid (Montiff INC, 2004). Glutamine actually accounts for 60% of the free amino acid pool in muscles and approximately 20% of the amino acid pool in plasma (Chwals, 2004). It assists as a significant metabolic and energy substrate in broad assortment of cellular reactions throughout the body (Chwals, 2004). It is also a regulator of protein production and is cellular fuel for tissues of the muscle, intestine, skin, and the immune system. In fact when muscle synthetic rates of glutamine are high, it serves as a major carrier of amino-nitrogen from muscles to the lungs. In the brain, it actually serves as a nitrogen transporter, which allows for the elimination of excess ammonia to help safeguard neuron-astrocyte interchange of amino acids and monoamines which, all in all, protects central nervous system functional integrity (Chwals, 2004). “Glutamine also helps control acid-base homeostasis by facilitating renal ammoniagenesis” (Chwals, 2004, 833). Glutamine has also been shown to be important in cell growth, most importantly in rapidly replicating cell population such as lymphocytes, fibroblasts, and enterocytes which use it as a favored source of fuel (Chwals, 2004). This could explain why glutamine has been known to help boost the immune system especially those seen in recovering patients after surgery.
What are the Benefits of Supplementing with Glutamine in Athletes and Post Surgical Care?
Glutamine is seen used more when the body undergoes times of physical and metabolic stress which could range from injuries such as burns, infections to exercise, fasting, and malnutrition (Chwals, 2004). Even though glutamine, as mentioned above, is a non-essential amino acid, when times of physical and metabolic stress occur and the demand for glutamine exceeds the body’s ability to supply it, it can become an essential amino acid (Chwals, 2004). When this happens muscles are completely deprived of glutamine along with other amino acids necessary to create glutamine necessary for protein synthesis. This can conclude to a negative nitrogen balance and catabolism. There is research stating that up to 50% decrease in glutamine levels during catabolic stress. Supplementing with glutamine can increase glutamine pools during times of stress as mentioned above (Montiff, 2000). “This can help increase protein synthesis and nitrogen balance and provide the anabolic effects necessary to support the body during its times of stress” (Montiff, 2000, 1). Glutamine among athletes is recommended during times of high intensity activities which can deprive the body of its glutamine pools in the muscles. Along with a loss of glutamine in the muscles during times of physical stress, there is a decrease in branch chain amino acids necessary to synthesize glutamine. (Montiff, 2000, 2). With Glutamine's anabolic effects there is research stating that glutamine is glycogen and protein sparring (Rivera, 2010). Theoretically speaking if BCAA's are necessary for the production of glutamine but supplementation of Glutamine is present, BCAA's will be spared.
How Can One Consume Glutamine?
Glutamine can be found in powder forms along in capsules (Sam, 2009). Overall your body produces it on its own hence it’s a non essential amino acid. Though this is different for athletes undergoing high intensity training. “It is recommended that when taking a glutamine it should be taken sublingually (under the tongue) to increase assimilation into the blood stream and blood tissue” (Montiff, 2000, 2).
Can I Overdose on Glutamine and how much should I take?
There is not much known about the possible side effects of overdosing with glutamine. Theoretically taking too much glutamine would cause excess glutamate and ammonia. High levels of ammonia in the body could potentially cause a severe brain condition known as encephalopathy (disease of the brain that can alter brain functioning) could occur (Monson, Schoendstadt, 2008). If you decide to supplement with this amino acid recommendations range from 2-10 grams per day depending on body weight (Slooten, 2004).
Conclusion
Overall glutamine is made by your body so you really don’t need it in your diet. If you don’t regularly exercise or exercise at lower to more moderate levels of intensity, chances are you don’t need to supplement with glutamine. Keep in mind if you are training at high levels of intensity it wouldn’t be a bad idea to actually supplement with this amino acid.
References
Sam. (2009). Glutamine Supplementation Benefits of L-Glutamine. Retrieved November 6, 2010, from Weight Loss & Training.com: http://weightlossandtraining.com/glutamine-supplementation
Chwals, W. J. (2004). Regulation of the Celluar and Physiological Effects of Glutamine. Cleveland.
Montiff INC. (2004, April). Pure L-Glutamine.
Slooten, T. V. (2004). Men's Total Fitness. Retrieved October 24, 2010, from www.mens-total-fitness.com
Rivera, H. (2010). L-Glutamine Basics-Preserve Lean Muscle Mass. Retrieved November 15, 2010, from About.com: http://bodybuilding.about.com/od/supplementationbasics/a/glutaminebasics.htm
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How Nitrogen Balance is Maintained with Glutamine